Temperature, Nervous System, Homeostasis and The Reflex Arc

Question 1

What is homeostasis?

Answer 1

When the body uses so much energy because it must maintain a constant internal environment

Question 2

Why is water important in homeostasis?

Answer 2

To prevent Dehydration as it damaged cells

Question 3

How is water gained and lost? (Homeostasis)

Answer 3

Water is produced by the body during respiration and absorbed from food or drink

Question 4

What happens if the body has to little water?

Answer 4

Kidneys re absorb more water into blood and less volume of urine is produced (more concentrated)

Question 5

What happens if the body has too much water?

Answer 5

The kidneys re-absorb less water into blood and higher volume of urine is produced (less concentrated)

Question 6

What can mild dehydration cause?

Answer 6

Dizziness, a dry mouth and concentrated urine

Question 7

What is the normal body temperature?

Answer 7

37 degrees

Question 8

How is water lost from the body?

Answer 8

Exhaled air, sweat and urine

Question 9

What is body temperature monitored and controlled by?

Answer 9

The centre of the brain’s hypothalamus (thermoregulatory)

Question 10

What is the thermotegulatory do?

Answer 10

It contains receptors sensitive to the temperature of the blood

Question 11

What does skin contain?

Answer 11

Temperature receptors and it sends nervous impulses to the thermoregultaory centre

Question 12

When happens if body temperature is too high?

Answer 12

Blood vessels dilate (vasodilation), sweat is produced from the sweat glands and hair and hair erector muscles are relaxed

Question 13

What happens is body temperature is too low?

Answer 13

Blood vessels constrict (vasoconstriction), sweating stops, skeletal muscles contract (shivers) and hair and hair erector muscles stand on end to trap a layer of air

Question 14

How do we gain temperature?

Answer 14

• Movement and exercise
• Shivering
• Wearing extra clothing

Question 15

How do we lose temperature?

Answer 15

• No movement of exercise
• Sweating
• Removing extra clothing

Question 16

What is an example of a stimulus?

Answer 16

Light, sound, touch, pressure, pain, chemical or a change in position or temp

Question 17

Give an example of a receptor

Answer 17

Pancreas, eyes, ears, nose, mouth and skin

Question 18

Give an example of an effector

Answer 18

Muscles or glands

Question 19

What is vasodilation?

Answer 19

When blood vessels become wider

Question 20

What is vasoconstriction?

Answer 20

When blood vessels get narrower

Question 21

What does the nervous system do?

Answer 21

It enables humans to react to their surroundings and it’s a response to a stimulus as it automatically and rapidly reacts and to coordinate their behaviour and is passed though cells (neurons) as electrical impulses to the central nervous system (CNS)

Question 22

What is the central nervous system?

Answer 22

It’s the brain and spinal cord and it coordinated a the response of effectors which may be muscles contracting or glands secreting hormones (reflex action)

Question 23

What are Neurones?

Answer 23

They are specialised cells that conduct electrical impulses through the body

Question 24

What do neurons look like?

Answer 24

They are elongated cells consisting of a cell body and a long, thin axon

Question 25

What are motor neurons?

Answer 25

They transmit messages from the brain and spinal cord to the muscles and glands

Question 26

What are sensory neurons?

Answer 26

They transmit messages from sense receptors to the Brian or spinal cord

Question 27

What is the process of the nervous system?

Answer 27

Stimulus -> Receptors then receptors goes into the CNS through the sensory neurone, CNS uses the motor neurone to get to the effector then response

Question 28

What is a reflex?

Answer 28

A fast, automatic response to a stimulus

Question 29

Do reflex arcs travel through conscious parts of the brain?

Answer 29

No

Question 30

What neurone comes after the se Seth neurone in a reflex arc?

Answer 30

A relay neurone